BAGHDAD, Iraq — A car bomb killed at least 13 people Wednesday in a Shiite part of Baghdad, and the U.S. command announced the deaths of eight more American soldiers — some victims of a weapon the American command believes comes from Iran.

At least 44 Iraqis were killed or found dead nationwide Wednesday, according to police reports. The toll marked an uptick in the daily carnage as President Bush prepares for a showdown in Congress over the future of the U.S. mission.

The deadliest attack occurred when a roadside bomb exploded along a busy highway during the morning rush hour in the eastern Baghdad district of Baladiyat. A medic at a nearby hospital said 13 people died, but a police officer put the figure at 15.

Both spoke on condition of anonymity because they were not supposed to release the information.

“We heard a big explosion and I saw many people get injured — I was one of them,” a man who identified himself only as Amjed told Associated Press Television News from his hospital bed. His right shoulder was bandaged and left arm in a sling.

“We’re poor people, we’re already suffering enough from the hardships of life — and now this,” he said. “I’m fed up with those who plant bombs and target people.”

U.S.: Iran supplies bomb typeThree of the American soldiers were killed and two were wounded after their Humvee was hit Tuesday with an explosively formed penetrator, a type of bomb that the U.S. alleges Iran has been supplying to Shiite militias. Iran denies the accusation.

Two other U.S. soldiers were killed and another wounded in an eastern section of Baghdad on Wednesday during combat operations, the military said. Two other Americans were mortally wounded Wednesday in a blast in Salahuddin province north of the capital.

Another soldier was killed and two were wounded during fighting Tuesday in western Baghdad, the U.S. command said.

The bloodshed in mostly Shiite eastern Baghdad occurred a week after the country’s most powerful Shiite militia leader, cleric Muqtada al-Sadr, ordered his fighters to cease attacks for up to six months so he could restructure his Mahdi Army.

But U.S. commanders say renegade elements within the Mahdi Army have disregarded al-Sadr’s order and are continuing attacks on U.S. and Iraqi forces. The U.S. believes those groups are backed by the Iranians, a charge that the Islamic Republic denies.

Other alleged Iranian tiesEarly Wednesday, U.S. forces captured an Iraqi believed to be working with the Iranian Revolutionary Guards Corps’s elite Quds Force to supply Shiite militias with Iranian-made weapons, said Maj. Winfield Danielson III.

The suspect is also believed to have helped transport Iraqis to Iran for “terrorist training,” Danielson said in an e-mail. The military said it is believed that he is “closely linked to individuals at the highest levels” of the Quds Force.

The violence occurred five days before U.S. Ambassador Ryan Crocker and Gen. David Petraeus report to Congress about progress since the United States sent nearly 30,000 more troops to Iraq.

Democrats are considering ways to force a drawdown of troops if Bush decides to keep forces in Iraq through spring as expected. A showdown between congressional Democrats and the White House seems all but assured.

Al-Maliki tries to bolster CabinetWith political tensions rising, Prime Minister Nouri al-Maliki met behind closed doors in the holy city of Najaf with Iraq’s top Shiite cleric, Grand Ayatollah Ali al-Sistani, to brief him on efforts to revive his flagging government, crippled by walkouts by Sunni Cabinet ministers and Shiite followers of al-Sadr.

Shiite politicians such as al-Maliki never make major decisions without consulting al-Sistani, whose endorsement in the January 2005 election elevated Shiite political parties to power.

There was no comment from the reclusive al-Sistani or his associates. But al-Maliki told reporters he discussed prospects of bringing Sunnis back into the government or putting together an entirely new administration of nonpartisan technocrats — though emphasized it was currently only an “idea” that was being considered among others.

“We are still trying to persuade the (Sunni Arab) brothers to return to their ministries but it seems that they are not likely to do so,” he told reporters. “This, naturally, means the ministries cannot be left vacant.”

Disease fears in northElsewhere, officials in Sulaimaniyah announced that they had indefinitely postponed the start of classes for primary and secondary schools in an effort to prevent the further spread of cholera in the northern province.

Since the disease broke out in mid-August, nine people have died and some 70 others have been confirmed with cholera. Another 4,000 are suffering from symptoms like severe diarrhea and vomiting.

Cholera is a gastrointestinal disease that is typically spread by drinking contaminated water and can cause severe diarrhea. In extreme cases, that can lead to fatal dehydration. In this case, U.S. military medical officials have said the area water does not seem to be contaminated and it is not yet certain how it is being spread.